Manufacture of chromium compounds of azo dyestuffs



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Patented Jan. 15, 1924.

Learn UNITED STATES PATENT OFFICE.

FRITZ STRAUB AND RICHARD SALLMANN, 0F BASEL. SWITZERLAND, ASSIGNORS T0 SOCIETY OF CHEMICAL INDUSTRY IN BASLE, 0F BASEL, SVTI'I'ZERLAND.

MANUFACTURE OF CHIROMIUM COMPOUNDS 0!? A20 DYESTUFFS.

No Drawing.

To all Mimi/1. it may concern:

B itv known that we. Fm'rx S'rnavn and R-ICHARD SALLMANN, both citizens of the Swiss Republic, and residents of liasek' Switzerland. have invented new and useful lm n'ovcmcnts in the Manufacture of (hromium Compounds of .\Zo Dyestuffs. of which the following is a full, clear, and exact specification.

In the specifications of the United States Patent. No. 1,221,849. and of patent applica tion Sci". No. 453.430 is described the manut'acture of chromium compounds of tl7.()--El \'t stutl's containing groups capalileot being chromed by treating the drestutls either with alkali compounds of the trivalent chromium hydroxide (r(()ll) or with the complex compounds obtained ll causing chromium hydroxide in presence of an alkali to act on organic compounds containing more than one. hydroxyl group.

By the present invention these chromium compounds of dycstutfs may he made in a. very advantageous manner by uniting in a single operation the manufacture of the dye stutl' and that of its chromium derivative, namely by preparing the azod vcstutl' in presence of one or other of the chroming agents of the aforesaid specifications and then heating the product until the dycstutf t'ormed has been completely converted into its chromium compound,

The following examples illustrate the in- 41 parts oF caustic soda are dissolved in a mixture of 10.3 parts of chromium hydroxide, freshly precipitated, and 70 parts of wa ter heated to (7() (l. and contained in an iron boiler having a stirrer; there are added to the mixture 15 parts of {ii-naphthol and the whole is cooled to 15 C. 27.3 parts of the diazo-compound of 1amiuo-2 oxy-naphthalenc.4-sultonic acid are now introduced and the mixture is heated to 40 C. and kept at this temperature until the diam-compound has disappear-ml. 'lhe tcnuicraturc is now raised to and kept at T0 75 C. until the dye stutl' has hcen completclr transformed into its chromium compound. The niixt urc is then strougl diluted with water. the. excess of caustic alkali is neutralized with a mineral Serial No. 533,739.

acid and the dyestufi' is precipitated by means of common salt. it dyes wool blue.

Example 2.

20 parts of Salmon-4-cresol-6-sulfonic acid are diazotized in assmall as possible a. quantity of water and the diazotized solution thusobtaincd is introduced into a mixture of 11.0 parts of chron'iimn hydroxide, 57 parts of caustic potash. 14.? parts of {am-aphthol and 51 parts of water, prepared as described in the preceding exani 'llo and coo-led to 5 C. i'l'hen the diam-compound has disappeared the mixture is slightly heated and there are added 28 parts of caustic potash; the whole is then heated at T5 (1'. until the dyestutt is completely traushirmed into its chromium compound which may be. the case a l'tcr some hours. Dilution with water follows. the-excess of caustic. alkali is neutral ized with a mineral acid and the dyestntt is precipitated h v means of common salt. It dyes wool violet.

Earample 3.

it parts of caustic potash are dissolved in a mixture heated to 60'- 70 C. of 5.2 parts of freshly precipitated chromium hydroxide and 25 parts of water. 5.8 parts of glycerine are then added and the whole is boiled until complete solution has occurred. After.

dilution with about 3 parts of water 8.6 parts of LphonylS-methyl-ti-pyra.zolonc are added. The mixture is cooled to 5. 13.6 parts of the diam-compound of l-amino-2-0xynaphthalcneA-sultonic acid are introduced and the whole is stirred until the diazocmnpound has disappeared. The mixture is now boiled in a reflux apparatus until the dyestuff is completely transformed into its chromium compound. The, mixture is then diluted with a. littlewater, the excess of caustic alkali is neutralized with a mineral acid and the dytstufi' is precipitated by means of common salt. It dyes wool bluishred. f i

What we claim is The herein described manufacture of chromium compounds of size-dyestuffs eontaiuingz groups capable of being chromed. consisting in uniting in a single operation the manufacture of the dycstufi' and that oi its chromium compound by preparing the converted into its chromium compound. Witnesses:

azad estufl' in r senoe of alkali compounds 1922, in the presence of two subscribing of t v trivannt chromium hydroxide witnesses.

(INCH) and then heating the product of FRITZ ST RAUB.

the reaction until the dyestufi is completely RICHARD SALLMAN N.

In witness whereof we have hereunto FRIDA KURZ, signed our names this 15th day of February, AMAND FRAME. 

